Fatigue test

Fatigue tests or fatigue experiments normally comprise several tests during which materials, components, assemblies or entire systems are subjected to specific load profiles. They are used to ascertain the behaviour of materials or systems (vehicles, aircraft, machinery) that are subjected to alternating forces. Most fatigue tests take place on Bending, rotary bending or vibratory test machines.

During the tests, a defined average Force (under certain circumstances this may be zero) and an alternating force act on the test piece. Axial, torsional and bending forces can be applied. In most cases, fatigue tests are performed several times with identical samples and different load cycles. The test data is displayed graphically in stress-load cycle diagrams in which the number of cycles until failure is plotted against the amplitude of the cyclic stresses or the maximum/minimum stress.

The test setup is adapted to the relevant test piece, so fatigue tests can be extensive and require complex test equipment.